Process for preparing anatomical casts of human and animal organs



Patented Feb. 1938 V I v UNITED STATES PATENT OFFlCE PROCESS FOR PREPARING ANATOMICAL CASTS OF HUMAN AND ANIMAL ORGANS August Schumm'er, Glessen, and Ernst 'lromms v dori'l, Darmstadt, Germany, assignors to Riihm 6: Haas Company, Philadelphia, Pa., a corporation of Delaware No Drawing. Application January 14, 1936, Serial No. 59,092. In Germany January 15, 1935 Claims. (01. 35-20) This invention relates to a method for making methods generally known for the polymerization casts of the internal structure of human and of vinyl compounds. Oxygen yielding substances animal organs and more particularly to the use such as hydrogen peroxide, benzoyl peroxide etc. of a material for making such casts that is fluid may be used as catalysts.- Substances regulating 5 enough to penetrate the finest capillaries of the the polymerization process such as aldehydes, oil organ so that after the process is completed a of turpentine, solvents etc. can be incorporated perfect cast of all the capillaries and cavities with the poiymeriz'able liquid to influence the within the organ is produced. speed of polymerization to any desired extent as Up to the present there has been no entirely for instance to avoid bubbling and violent reac- 10 satisfactory method of producing such anatomitions of the injected substance. 10 cal casts of human and animal organs for pur- It is not necessary to maintain any particular poses of instruction and research. For lack of a temperature while injecting the substance into substance suillclently fluid to penetrate the most the organs to be reproduced. The substance fills intricate recesses and cavities, the anatomical out all the cavities completely without shrinking casts hitherto made have been too inaccurate and to any practical extent during the process of incomplete. solidiflcaticn so that it is not necessary to do It has now been found that practically perfect any supplementary injecting. The solidification casts of the internal structure of anatomical of the injected substance is performed by polyorgans showing the arrangement and size of all merization at temperatures which exclude a dethe capillaries and cavities can be made by information of the organs which form the mold. 2o jecting into the veins, arteries or other canals After polymerization the bones and tissues of of the organ an organic liquid which is capable the organ which has been used as the mold can of polymerizing to a solid substance, subjecting be destroyed by the action of acids or alkaline the material to polymerizing influences until substances. Neither of these has an injurious 26 polymerization is complete and then treating the effect on the polymerization product.

organ with chemicals which will destroy and re- The polymerizable material used for injecting move all natural tissue etc. but which will not into the arteries, etc. may be colored as desired affect the polymerized material. by the use of a small amount of soluble dyestufi.

The polymerizabl'e liquids which are suitable Thus, for any given organ a cast of the arteries 30 for the purposes of this invention belong to the may be made with a red material and one of the 30 class of vinyl compounds and include the lower veins with a blue material. For this purpose two aliphatic esters of acrylic and methacrylic acids, like organs will be necessary, one for the arteries vinyl acetate. etc. Mixtures of these liquids may and one for the veins. also be used. These compounds which on poly- It is not possible to give any definite directions merization yield solid or rubber-like polymers are for determining the exact end-pointer the in- 35 most satisfactormand we prefer to use methyl jection. In filling the arteries, for example, it is methacrylate, ethyl methacrylate, methyl acrypossible that some of the material will enter the late and vinyl acetate or mixtures of these. In veins and the only way that the correct filling some cases a higher ester such as butyl acrylate can be judged is by the skill and experience of can be used in conjunction with the materials the operator. In filling cavities closed at one 40 just enumerated. For some purposes it is deend it is suggested that a very small opening be sirable to employ a liquid having a viscosity made at the point farthest from the point of somewhat higher than the monomeric material injection seats to permit escape of air, etc. A in which case the initial liquid may be partially syringe with a plunger is recommended and one polymerized before injecting it into the canals of which does not have too great a diameter. It is 45 the organ. Other materiais such as cellulose also recommended that the syringe be operated esters, cellulose ethers, colophony, etc. may be byhand so that the operator can become accusdissolved ,in the monomeric liquid to increase its tomed to the feel of the operation and thus beviscosity. come skilled in judging when the proper end- Methyl methacrylate forms the hardest polypoint has been reached. 50 mar of the materials enumerated above and for The new method has the following advantages this reason is the preferred liquid for injecting over the methods heretofore applied: The visinto the canals of the organ. cosity' of the susbtance to be injected may be The'polymerization oi the methyl methacrylate varied easily as d s ibe It 18 not n ry or other polymerizable liquid is carried out by the to do any supplementary injecting. The method 55 permits clean work and is easy to apply. The solidified product is resistant to an extremely high degree against the action of moisture, changes of temperature and against mechanical action: limited durability. They show the most intricate recesses and cavities of the organs they reproduce, even vessels of microscopic size can be reproduced properly.

In order that the invention may be fully understood, the foliowing examples are given by way of illustration only.

Example 1 Methacrylic acid methyl ester is boiled up with 0.01% of a suitable oxygen producing polymerization catalyst and heated until the fiuid has a syrup-like consistency. This material is injected in known manner into the arteries of any desired organ. After completely filling the arteries to be reproduced, the injection opening is bound up and the organ is heated up to a temperature of about 45 C., for example in a water bath, until the injection mass is hardened which generally occurs after 1-2 days. By treating the organ with 25% potassium hydroxide solution to remove the tissue and hydrochloric acid to remove the bony material, if any is present, the clean cast showing the complete structure of the arteries is obtained.

Example 2 Methacrylic acid methyl ester, which contains parts by weight 'of dibutyl phthalate is boiled up with 0.01% of a suitable oxygen producing polymerization catalyst and warmed until the fiuid has a syrup-like consistency. The material is used and treated further as described in Example 1.

, Example 3 cavities of the organ with a polymerizable organic substance capable of forming a hard polymer, solidifying said substance by subjecting it to The products are of practically unpolymerizing influences and subsequently treating the organ with chemicals which destroy the natural material thereof without affecting the polymerized material.

2. The process for preparing anatomical casts of the interior structure of human and animal organs which comprises filling the canals and cavities of the organ with at least one polymerisable derivative of one of the group consisting of acrylicand methacrylic acids capable of forming a hard polymer solidifying said derivative by subjecting it to polymerizing influences and subsequently treating the organ with chemicals which destroy the natural material thereof without affecting the polymerized material.

3. The process for preparing anatomical casts of the interior structure of human and animal organs which comprises filling the canals and cavities of the organ with at least one polymerizable derivative of one of the group consisting of acrylic and methacrylic acids capable of forming a hard polymer, solidifying said derivative by heating the organ and its contents to about 45 C. and subsequently treating the organ with chemicals which destroy the natural material thereof without affecting the polymerized material.

4. The process for preparing anatomical casts of the interior structure of human and animal organs which comprises filling the canals and cavities of the organ with a polymerizable substance comprising essentially methyl methacrylate and solidifying said substance by subjecting it to polymerizing influences and subsequently treating the organ with chemicals which destroy the natural material thereof without aflecting the polymerized material.

5. The proeessfor preparing anatomical casts of the interior structure of human and animal organs which comprises filling the canals and cavities of the organ with a polymerizable substance comprising essentially a mixture of methyl methacrylate and butyl acrylate and solidifying said substance by'subjectlng it to polymerizing influences and subsequently treating the organ with chemicals which destroy the natural material thereof without aflfecting the polymerized material.

AUGUST SCHUMMER. ERNST 'I'BQMMSDORI'T. 

